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UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



the nymphs only. It will, of course, kill a few adults, but the number 

 of these will be very small. In addition to the adults which escape, 

 there are eggs at this time which the spray will not prevent from 

 hatching. While this means of control will kill a very satisfactory 

 percentage of the nymphs, many adults will escape, and the eggs will 

 be left to hatch later. 



The advantage of the cage method is that it is more thorough and 

 effective. The hoppers are attacked at a critical time; i. e., when all 

 adults are in the vineyard; and as they have not commenced to breed 

 or to lay eggs the work is effective in greatly diminishing the numbers 

 of succeeding generations. 



THE IMPORTED GRAPE-ROOT WORM. 



(Adoxus vitis Fourcroy.) 



This pest of the vine has been reported from different parts of the 

 State for a number of years, but until a year or two ago it was unknown 



as a root feeder. In 

 our literature it has 



/ commonly gone by the 



name of flea beetle, 

 and probably most 





I, 





growers know it by 

 that name. It is not, 

 however, a flea beetle 

 at all, since it neither 

 jumps as indicated by 

 the name, nor is its 

 life history similar to 

 that of a flea beetle. 



It was called by 

 Matthew Cooke, in his 

 book entitled "Inju- 

 rious Insects of the 

 Orchard and Vine- 

 yard," the " Imported 

 Grape Flea Beetle." 

 Since, however, it is 

 a root beetle rather than a flea beetle and is probably an imported 

 insect, and in its life history is almost identical with the grape-root 

 worm of the Eastern States, we propose giving it the common name of 

 Imported Grape-Root Worm. 



FIG. 5. Adult of the grape-root worm. 



